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24 tháng 11 2017

they join in spring activities program

What program do they join in?

they plant and water trees along the streets on weekends

When do they plant and water trees along the streets?

​đặt câu hỏi cho phần in nghiêng

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken trees clearly heard distress calls. According to one of the scientists, most parched trees transmit their plight in the 50-hertz to 50kilohertz range. (The unaided human ear can detect no more than 20 kilohertz). Red oak, maple, white pine, and birch all make slightly different sounds in the form of vibrations at the surface of the wood.

 

   The scientists think that the vibrations are created when the water columns inside tubes that run along the length of the tree break, a result of too little water following through them.

 

   These fractured columns send out distinctive vibration patterns. Because some insects communicate at ultrasonic frequencies, they may pick up the trees' vibration and attack the weakened trees. Researchers are now running tests with potted trees that have been deprived of water to see if the sound is what attracts the insects. “Water-stressed trees also smell differently from other trees, and they experience thermal changes, so insects could be responding to something other than sound”, one scientist said.

Question: All the following are mentioned as possible factors in drawing insects to weakened trees EXCEPT______.

A. thermal changes

B. sounds

C. changes in color

D. smells

1
16 tháng 1 2017

Đáp án C.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken trees clearly heard distress calls. According to one of the scientists, most parched trees transmit their plight in the 50-hertz to 50kilohertz range. (The unaided human ear can detect no more than 20 kilohertz). Red oak, maple, white pine, and birch all make slightly different sounds in the form of vibrations at the surface of the wood.

 

   The scientists think that the vibrations are created when the water columns inside tubes that run along the length of the tree break, a result of too little water following through them.

 

   These fractured columns send out distinctive vibration patterns. Because some insects communicate at ultrasonic frequencies, they may pick up the trees' vibration and attack the weakened trees. Researchers are now running tests with potted trees that have been deprived of water to see if the sound is what attracts the insects. “Water-stressed trees also smell differently from other trees, and they experience thermal changes, so insects could be responding to something other than sound”, one scientist said.

Question: Which of the following is the main topic of the passage?

A. The effect of insects on trees.

B. The vibrations produced by insects.

C. The mission of the U.S Forest Service.

D. The sounds made by trees.

1
9 tháng 6 2018

Đáp án D.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken trees clearly heard distress calls. According to one of the scientists, most parched trees transmit their plight in the 50-hertz to 50kilohertz range. (The unaided human ear can detect no more than 20 kilohertz). Red oak, maple, white pine, and birch all make slightly different sounds in the form of vibrations at the surface of the wood.

 

   The scientists think that the vibrations are created when the water columns inside tubes that run along the length of the tree break, a result of too little water following through them.

 

   These fractured columns send out distinctive vibration patterns. Because some insects communicate at ultrasonic frequencies, they may pick up the trees' vibration and attack the weakened trees. Researchers are now running tests with potted trees that have been deprived of water to see if the sound is what attracts the insects. “Water-stressed trees also smell differently from other trees, and they experience thermal changes, so insects could be responding to something other than sound”, one scientist said.

Question: It can be inferred from the passage that research concerning the distress signals of trees______.

A. has been unproductive up to now

B. is no longer sponsored by the government

C. was conducted many years ago

D. is continuing

1
9 tháng 9 2019

Đáp án D.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

  It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken trees clearly heard distress calls. According to one of the scientists, most parched trees transmit their plight in the 50-hertz to 50kilohertz range. (The unaided human ear can detect no more than 20 kilohertz). Red oak, maple, white pine, and birch all make slightly different sounds in the form of vibrations at the surface of the wood.

 

   The scientists think that the vibrations are created when the water columns inside tubes that run along the length of the tree break, a result of too little water following through them.

 

   These fractured columns send out distinctive vibration patterns. Because some insects communicate at ultrasonic frequencies, they may pick up the trees' vibration and attack the weakened trees. Researchers are now running tests with potted trees that have been deprived of water to see if the sound is what attracts the insects. “Water-stressed trees also smell differently from other trees, and they experience thermal changes, so insects could be responding to something other than sound”, one scientist said.

Question: It can be inferred from the passage that research concerning the distress signals of trees______.Which of the following could be considered a cause of the distress signals of trees?

A. attacks by insects

B. experiments by scientists

C. torn roots

D. lack of water

1
25 tháng 4 2019

Đáp án D.

9 tháng 4 2019

Fewer hoặc less

1) they work.fewer..hours than us a day

2) Susan likes her new life in Ha Noi now. She writes.fewer..letters home

3) You should spend .less. time watching TV

4) He has ..fewer.days off than anyone in the factory

5) Lan drinks .less..water than Hoa a day

6) There are.fewer..trees along the strees in the new town

7) I get ..less..money than him

8) Lan spends ...less. money on books than Kien

9) They are very tired. They can do .fewer... exercises this evening

10) They are very tired. They will do .less..work tonight

11 tháng 5 2017

1/She likes camping on the weekend.

2/No, she doesn't.

3/ She usually goes with her friends.

4/They always take food, water and a camping stove.

11 tháng 5 2017

ĐÚNG KHÔNG VẬY CHỊ

13 tháng 1 2018

change these sentences into passive

1.they separated the rice from the husk

=> The rice was seperated from the husk.

2.the boys made a fire by their camp

=> A fire was made by their camp by the boys.

3.they build this house more than on hundred years ago

=> This house was built more than one hundred years ago.

4.every year VietNam export millions of tons of rice

=>Every year millions of tons of rice are exported

5.VietNamese people celebrate theri Lunar New year around January of February

=> The Lunar New Year is celebrated by Vietnamese people around January of February.

6.After Tet holiday VietNamese people usually plant trees in theri neighborhood

=> After Tet holiday, trees are usually planted in their neighborhood.

7.how many festivals do you clerabate in your community?

=> How many festivals are celebrated in your community?

8.how many motorbikes does Viet Nam import a year?

=> How many motorbikes are imported by Vietnam a year?

9. The publisher his book in 1996?

=> His book was published in 1996

10.they repaired our desk during the weekend

=> Our desk was repaired during the weekend.

13 tháng 1 2018

change these sentences into passive

1.they separated the rice from the husk

=> The rice was seperated from the husk.

2.the boys made a fire by their camp

=> A fire was made by their camp by the boys.

3.they build this house more than on hundred years ago

=> This house was built more than one hundred years ago.

4.every year VietNam export millions of tons of rice

=>Every year millions of tons of rice are exported

5.VietNamese people celebrate theri Lunar New year around January of February

=> The Lunar New Year is celebrated by Vietnamese people around January of February.

6.After Tet holiday VietNamese people usually plant trees in theri neighborhood

=> After Tet holiday, trees are usually planted in their neighborhood.

7.how many festivals do you clerabate in your community?

=> How many festivals are celebrated in your community?

8.how many motorbikes does Viet Nam import a year?

=> How many motorbikes are imported by Vietnam a year?

9. The publisher his book in 1996?

=> His book was published in 1996

10.they repaired our desk during the weekend

=> Our desk was repaired during the weekend.